Current Trends in Mass Spectrometry

Biography

Biography: RuAngelie Edrada-Ebel

Abstract

High resolution Fourier transform mass spectrometry (HRFTMS) was employed as complimentary metabolomic tool to dereplicate chemical profiles of sponge-associated microbes. Sponges act as hosts to a diverse population of symbiotic organisms including bacteria and fungi. These symbionts offer benefits to the host including protection, nutritional benefit and support to the sponge skeleton. They have also been recognised as an important source of secondary metabolites which may have bioactivity and therefore medicinal potential. The innovative strategy involved targeted cultivation and isolation of biologically active compounds. Principal Component (PCA), Hierarchical Clustering (HCA), and Orthogonal Partial Least Square-Discriminant (OPLS-DA) analyses were used to evaluate HRFT mass spectral data of culture extracts. The results of the statistical analysis identified and validated the best culture conditions and extraction procedure which optimized the isolation of novel bioactive metabolites. Production of secondary metabolites were investigated in several of the bacterial symbionts that were isolated from marine sponges. Novel secondary metabolites were screened using high resolution mass spectrometry-based metabolomics approaches. Metabolomic profiling using HR-ESIFTMS-MS fragmentation were done at different stages of the growth phase for both solid and liquid culture media and subjected to molecular networking. Molecular networking the mass fragmentation data pinpoints functionalities that can be correlated to bioactivity and fermentation parameters as well as to predict and enhance the biosynthetic pathway involved in the production of the target secondary metabolite. Dereplication studies were accomplished by utilizing the Mzmine software with Antibase and DNP databases. The optimised method in terms of media, incubation time, and maximum production bioactive compounds are taken into account for the scale-up. Metabolomic- and bioassay-guided isolation approaches were carried out to target the compound(s) of interest. We apply a similar approach on terrestrial endophytic fungi. Endophytic fungi also represent a potential source of novel chemistry and biology.